Qemu problems in -next with 's390/spinlock: add niai spinlock hints'

From: Guenter Roeck
Date: Tue Jul 25 2017 - 21:15:03 EST


Hi Martin,

my s390 qemu tests in linux-next stopped working a few days ago.
Bisect points to commit 's390/spinlock: add niai spinlock hints'.

Looking at the patch, this isn't really surprising; at least to me it looks
like the patch is making instructions mandatory which are only available in
Z14 CPUs. Does this mean that older s390 CPUs (such as the Z900 used in my
qemu tests) are no longer going to be supported in Linux ?

Thanks,
Guenter